Game as the Queen, wearing top with a low bust (5,4)
I believe the answer is:
water polo
'game' is the definition.
(water polo is a kind of game)
'top with a low bust' is the wordplay.
'top' becomes 'polo' (polo top).
'with' says to put letters next to each other.
'a low bust' becomes 'water' (I am not sure about this - if you are sure you should believe this answer much more).
'polo' after 'water' is 'WATER-POLO'.
'as the queen wearing' acts as a link.
This may not be correct. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for water polo that I've seen before include "Swimming pool game" , "Game played by teams of swimmers with large ball" , "event" , "Seven-a-side game involving swimming" , "Sport for swimmers" .)